Snow Accumulation in the Talos Dome Area: Preliminary Results

Abstract

Determining snow accumulation is one of the principal challenges in mass balance studies and in the interpretation of ice core records. Accurate knowledge of the spatial distribution of snow accumulation is fundamental for understanding the present mass balance and its implication on sea level change, for reliable numerical simulation of past and future ice sheet dynamics, and for creating atmospheric climate models. Depth-age models for deep ice cores require knowledge of the temporal variability of snow accumulation. Accumulation of snow principally results from precipitation of snow and its redistribution/ablation by wind at the surface (Frezzotti et al., 2004a). Chemical and isotopic analysis of ice cores reveals seasonal and annual signals. However, these signals may not be representative of annual snow accumulation or of the annual chemical/isotopic composition of snow. Talos Dome (TD, 72°48’S; 159°06’E, 2316 m, T -41.0 °C) is an ice dome on the edge of the East Antarctic plateau, about 290 km from the Southern Ocean and 250 km from the Ross Sea (Fig. 1). An ice core is currently being drilled at this site (Frezzotti et al., 2004b) within the framework of the Talos Dome Ice Core Project (TALDICE). In order to provide detailed information on the temporal and spatial variability of snow accumulation, research was conducted at Talos Dome and along a North-South transect (GV7-GV5-TD-31DPT) in the framework of the ITASE programme. The 400 km-long transect follows the ice divide from the Southern Ocean to Talos Dome, and then continues in a southward direction towards Taylor Dome. Stake network measurements, ice core analysis and snow radar surveys along the transect have provided detailed information for reconstructing the temporal (annual) and spatial (meter scale) variability of snow accumulation over the last 200 years at the km scale.